A lighting module is known, for example, from EP 1 357 334. The embodiment illustrated by FIG. 4 corresponds to a solid optical piece that can be produced by molding from transparent material. However, to allow reflection of the light rays emitted by the source in the reflection volume delimited by the reflector, the external surface of the reflector and folder means is coated with a reflective material.
The placing of the reflective coating, for example by aluminizing, is relatively tricky and expensive.
The aim of the invention is in particular to provide a lighting module giving a beam with cut-off line which requires no reflective coating, in particular no aluminizing, and which requires only a few assembly operations, so as to eliminate the critical operations and tolerances.
This is because an operation of deposition of a reflective coating creates losses by specular reflection. An assembly operation creates imprecisions in relative positioning of the various parts.